I think that it is geometry.
E=Z*sqrt (p(1-p)/N), where E= error margin, p=proportion, N=sample size
Katrina's margin error at 85% confidence interval: E=1.96*sqrt (p(1-p)/100) = 0.196 sqrt (1(1-p))
Mathew's margin error at 99% confidence interval: E= 2.58*sqrt (p(1-p)/400) = 0.129 sqrt (p(1-p))
Since both obtained same estimate of proportion (that is, value of p), it can be seen that Mathew's estimate will have a small error (That is, 0.129 is smaller than 0.196). This can be attributed to larger sample size although a wider confidence (99%) interval was considered.
Lets see!
We need to use the pythagorean theorem (a^2+b^2=c^2) to check.
So..
15^2+ 17^2 = 19^2
225+ 289= 361
Hm 225 and 289 do NOT equal 361 therefore it is NOT a right triangle.
Rent and electricity = 5x + 11
rent = 2x - 3
electricity = (5x + 11) - (2x - 3)
electricity = 5x + 11 - 2x + 3
electricity = 3x + 14
---------------------------------
Answer: 3x + 11
---------------------------------
Answer:
Possibly meters or feet/yards.
A walk through a neighborhood would be less than a mile/kilometer but much further than an inch/centimeter.